First-run breeding bird atlases establish a baseline for detailed avian range maps. However, a single atlas provides no information on changes in distributional status over time. Maryland and D.C. have undertaken a second atlas to document two decades of change since the 1987 completion of the first MD/DC atlas. This project started in 2002 and is now entering its fourth and penultimate field season. Thus far, data has been collected in 1109 five km2 atlas blocks with 204 species reported, 175 of them confirmed as breeders. Several grassland and mature forest Neotropical migrant birds appear to have seen some range shrinkage over the last two decades. Here we present several examples of distributional change detected between the two MD/DC atlas projects and discuss what still needs to be achieved over the last two years of the current project.
Additional Publication Details
Possible distributional changes detected by a second breeding bird atlas in Maryland and the District of Columbia
Wilson Ornithological Society and Association of Field Ornithologists Joint Meeting, April 21-24, Beltsville, Maryland. Abstracts